This section introduces aspects that may be helpful in facilitating a better understanding of the invention(s). Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
Mobile communication for Public Safety and Disaster Recovery (PSDR), as used for example by police, fire and rescue services, are based on communications systems known as Professional Mobile Radio (PMR) or Land Mobile Radio (LMR). However these systems may provide restricted bandwidth services so there is some intent to move towards providing such services using mobile networks based on Long Term Evolution (LTE) and LTE-Advanced (LTE-A) cellular radio technology, which may provide higher bandwidth and higher data rate services.
A nationwide rollout of broadband networks based on LTE for PSDR in parallel to deployed commercial cellular networks may be considered inefficient regarding costs involved.
Document EP 2 670 206 A1 discloses methods and network elements partitioning at least a subset of contention based resources for random access attempts into a plurality of partitions. Document US 2007/0211787 A1 describes a concept which may serve to improve spreading channel code selection in wireless technologies that employ two-stage ranging. Document EP 1 954 087 A1 outlines method and apparatus for reducing collisions during an access procedure between a plurality of user equipments in a radio communication system. Document US 2007/0297367 A1 is concerned with ciphering of signaling messages.